JBA UCA Balljoint bolt break

Hello everyone, I’m in the process of installing my JBA UCA’s on my 2009 trd off-road. The included directions say to check that the 4 balljoint bolts are at 20 ft pounds. I did this to both sides with no issues on the passenger side but on the driver side all 4 bolts snapped before I ever got to 20 ft pounds. Also according to the marks on the bolt it appears to be a grade 7. So my question is has anyone had any similar experiences with the balljoints that bolt into the JBA UCA’s and would upgrading to grade 10 bolts make a difference or do I need to stay with the softer ones? Thanks.

edit: the chart I was looking at was wrong, I had grade 5 hardware and ended up grabbing some grade 8 bolts.

 

What markings on the bolt, done believe there is a grade seven or a ten. If they have 3 marks, they are grade 5 bolts.

 

Three lines on top of bolt. I wasn’t sure how to read them so I only went off a diagram I found on another post here. I ended up grabbing some grade 8 at my local store, would of had to order the 10’s. I discovered a few pieces or slag or some other excess metal that was inside the holes and powder coated over. Once I cleaned the holes out with a drill bit they all went in perfect.
You can see a one in the upper hole in the attached photo. My only guess was I torqued them from the top and the threads got hung on that.

 

Looking more into it the chart I was using is not aligning with anything else I have seen online. I’m thinking these are not grades but I believe there is another rating system.

 

Here you go

 

Awesome, that makes much more sense than what I had for reference.

 

Do you have dimensions of bolts/nuts you used? 2 of mine got too much twerk attention and busted

 

Did you torque the nut or the bolt itself? You should always torque the nut but if you have to torque the bolt the torque is less. I just got my rusty ball joints replaced with his cerakoted ones and I swapped out the hardware for grade 8 stuff just to be cautious but I think Marlin did his homework and that is why he chose what he did.

 

I may have over-torqued, I remember the specification was on the very low end of my smallest torque wrench, it may have been inaccurate...

I’m trying to source some new hardware, what did you go with?

 

I just took an unbroken one in and matched the width and length to something stronger I don't remember the size exactly. One thing that I did notice is that the bolts that were originally in there were just long enough for the nut. The new ones that came with the replacement BJ's were a little longer so I went with the longer size.

 

Just tighten the damn things until they are good and tight.

Seriously. They aren't going to vibrate themselves loose and clearly 20 ft lbs is a garbage torque spec straight from the manufacturer..

 

I don’t want to pull the “parking lot
mechanic” move at fastenal but I will do what i gotta do...

For the sake and purpose of this thread it would be nice to have included the thread pitch/length/grade of replacement hardware. Or part#